(1) Field of the Invention
The present invention relates to shaping molds and a process for shaping ceramic articles by using such shaping molds. More particularly, the invention relates to shaping molds each comprising a non-permeable mold of which the molding surface is partially made of a material having a contact angle of not less than 80.degree. for water, and also to a process for shaping ceramic articles by using such shaping molds.
(2) Related Art Statement
As processes for producing ceramic-shaped bodies having relatively complicated shapes, injection molding, pressure casting, and wet type pressing have heretofore been known.
In the injection molding, ceramic-shaped bodies are obtained by mixing a ceramic powder with an organic binder comprising a resin such as polyethylene or polystyrene and wax, shaping the thus obtained raw material mixture by injection molding, and dewaxing the shaped bodies.
In the pressure casting, ceramic-shaped bodies are obtained by mixing a ceramic powder, water and a shaping assistant such as a deflocculant to obtain a slip, pouring the slip into a casting mold, and casting it under pressure.
In the wet type pressing, ceramic-shaped bodies are obtained by mixing and kneading a ceramic powder, water, and a shaping assistant such as a binder, deairing the mixture in vacuum to obtain a body, placing the body in a mold, and pressing it.
However, the above-mentioned conventional injection molding technique has a shortcoming in that it takes a long time to dewax shaped bodies obtained by the injection molding.
The pressure casting and the wet type pressing have unfavorably poor shape retention after the shaping and bad mold releasability.